[Cutaneous large B-cell lymphoma of the leg]

Large B-cell lymphoma of the leg (LBCLL) accounts for 2 % of primary cutaneous lymphomas, and the EORTC considers it to be of intermediate prognosis. It usually presents in elderly patients, and manifests clinically as erythematous nodules or tumors, often unilateral, on the lower third of the legs. On rare occasions, it presents with extracutaneous dissemination. We present the case of a 77-year-old male who consulted his physician because of an asymptomatic indurated erythematous papule which had appeared one month earlier on his left leg and had quickly and progressively increased in size. Concurrently, other similar lesions had been appearing on the thigh and back of the same leg. Histological analysis detected a large cell lymphoid infiltrate positive for CD20 and bcl-2 throughout the dermis. The extension study was normal. The patient was treated with an intravenous infusion of rituximab for four consecutive weeks, with full remission of the lesions.